20972159 has 8 divisors (see below), whose sum is σ = 23567712. Its totient is φ = 18516960.

The previous prime is 20972141. The next prime is 20972167. The reversal of 20972159 is 95127902.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20972159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20972129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34772 + ... + 35369.

It is an arithmetic number, because the mean of its divisors is an integer number (2945964).

Almost surely, 2^20972159 is an apocalyptic number.

20972159 is a deficient number, since it is larger than the sum of its proper divisors (2595553).

20972159 is a wasteful number, since it uses less digits than its factorization.

20972159 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70177.

The product of its (nonzero) digits is 11340, while the sum is 35.

The square root of 20972159 is about 4579.5369853294. The cubic root of 20972159 is about 275.7704411659.

The spelling of 20972159 in words is "twenty million, nine hundred seventy-two thousand, one hundred fifty-nine".